CRMS hydrology data including water elevations and inundation depth, have been adjusted relative to the most recent coastwide elevation survey.
Adjusted data are identified as Geoid 12b throughout CRMS data products. The CRMS website is being updated to incorporate these changes.

Other data types are not affected by this update.

While CRMS website updates proceed, the best source for CRMS hydrology data is CIMS. All Geoid 12b data are currently available for download (here)
In 1990, the U.S. Congress enacted the Coastal Wetlands Planning, Protection, and Restoration Act (CWPPRA) in response to Louisiana's land loss crisis. From 1990 to 2018 the CWPPRA Program, a joint federal and state effort, has authorized 214 coastal restoration and protection projects. The restoration techniques used include: freshwater and sediment diversion, dredged material placement for marsh creation, shoreline protection, terracing, hydrologic restoration, barrier island restoration, and vegetative planting.
The Coastwide Reference Monitoring System (CRMS) was designed to monitor the effectiveness of restoration actions at multiple spatial scales from individual projects to the influence of projects on the entire coastal landscape. The CRMS design includes a suite of sites encompassing a range of ecological conditions in swamp habitats and fresh, intermediate, brackish, and salt marshes. Approximately 390 sites are monitored using standardized data collection techniques and fixed sampling schedules. CRMS sites are located within or outside of CWPPRA restoration and protection projects. The CRMS reference network approach allows for comparisons of changing conditions at CRMS sites within and outside of restoration and protection projects.

Any Questions, contact: crms@usgs.gov